Poul Anderson - A Midsummer Tempest

“By right of blood alone—a stuff more thick than water, goes the adage, but too thin to mortar soil in firmness’neath my claim,” the prince answered wryly. “At present, as the nephew of King Charles, I’m fighting on his side against revolt. Mine English friend and I were lorn in Wales, beset by Puritans and other dogs, when we got… guidance… to this happy place.”

Valeria sat upright. “Wait a minute! King Charles—Puritans—you mean Roundheads?” (He nodded.) “ When are you from? I mean, what date would you say it is?”

“Why-y… I’ve lost track of what it is exactly—but August, sixteen hundred forty-four—”

“Ahhh,” she exulted. A slender fist clenched on the arm of her chair. “How much do you know about the situation—parallel universes and all that jazz—Nothing, h’m? Well, look, Rupert, I’m from America. You know America, don’t you? Where I come from, it’s independent countries. And… when I left home, the year was 1974. Holger, there, left in 1950—but not the same 1950 as I was busy being born in.”

Rupert grew most quiet. “This well’s too deep for Will,” complained Fairweather. Turning to Clodia, who was obviously furious that neither Rupert nor Holger paid her any special heed, he added slyly, “And eke for thee?” Her glance crossed his and came to rest.

Taverner leaned back, ankles crossed, fingers bridged, altogether delighted. The fire was burning down. A gnomish figure bustled from the kitchen doorway to lay on more wood. The barmaid took empty vessels with an equal clatter, filled and returned them.

“You’re from tomorrow, then,” Rupert said low, “as Clodia is from the ancient past; and distant lands?”

“Not quite,” Valeria denied. “I’m not sure how well I can get the idea across, but I’ll try. Look, you were born into the world you know. It has such-and-such qualities—geography, astronomy, laws of nature, kinds of life; people, nations, societies; a past, a present, and a future growing out of these, Right?” (Rupert nodded.) “Well, imagine some important event had turned out differently in the past. A battle lost instead of won, that kind of thing. Give me an example.”

Rupert’s bewilderment was yielding to fascination. He cast a look at Holger while he tugged his chin.

Finally: “Well, say Prince Hamlet had not died in vengeance, thus making Fortinbras the Danish king, but had, instead, become the king himself. That dynasty had many English ties. He might have come and helped his kinfolk here to overthrow Macbeth, the Scots usurper. Once planted on the isle, the Danes might next remember King Canute, not long agone, and turn on Norman William when he came. Since Denmark only, of the Northern lands, had cannon then, however primitive—”

“Hvad for Pokker?” burst from Holger.

“Take it easy,” Valeria told him. “He’s from a different time-line… I wonder, I wonder—” Fairly aflame with enthusiasm, she leaned forward. “Let’s get the theory of this out of the way first, shall we, Rupert?”

Will saw his leader struggle for insight, remarked to Clodia, “I thank tha Loard I war not boarn to think,” and clinked his tankard against her wine-glass. She smiled straight at him. He choked, “I ne’er wot one could stagger in a chair.”

Valeria was proceeding: “Well, if you can imagine history might have switched onto a different track, take the next step. That is, suppose both outcomes are real. One world where, uh, Hamlet died young; one where he went on to take the Danish crown and stop the Norman conquest. Both happened. Can you accept that?”

“I dare not say what limits God has laid on His creating,” Rupert breathed. “But how can this be?”

“Two whole universes… two whole space-time universes, stars, galaxies, countless planets—differing in a single detail, and of course in the consequences afterward—Except it isn’t like that, really. These universes have always been distinct, from the beginning. It’s just that this is the first point where the differences between them get noticeable. Besides, we haven’t got merely two universes. Nobody’s proved, in my world, whether there’s an infinity of them, or whether the number’s finite but enormous—N factorial, to be exact, where N is the total number of matter and energy particles that exist… You can picture the cosmoses as lying parallel to each other, like the leaves in a book. That isn’t strictly true, either; they occupy the same space-time, being separated by a set of dimensions—”

“Hold on, Valeria,” said Holger. “Have pity. You’re close to losing me overboard, and poor Rupert looks as if he’s going down for the third time.”

The girl relaxed and laughed at herself. “Sorry. You’re right. Uh, Rupert, think of it this way. A lot of different worlds. Some almost the same as yours, some totally alien to it. In some, for instance, there’s a kingdom of England, A.D. 1644; in others the date is different; in still others, the kingdom never existed.

Even the laws of nature may vary. What’s possible in one world is not in another, and vice versa. You follow me?”

Rupert ventured a smile. “Through quicksands, marshes, brambles, rain, and night.”

“And if a person knows how, he can cross between them,” Valeria continued. “You savvy? After all, this is a pocket universe you’re in.”

Rupert drank deep. “At least its beer speaks comforting of home,” he said to Taverner, “though sweeter, like a long-forgotten dream.”

“I know what’s sweeter, aye, a sugartit,” Will whispered. He squeezed Clodia’s hand. After a glance at oblivious Rupert and Holger, she gave a shrug, which quivered in numerous places, and fluttered her eyelids.

“You are from… elsewhere, Mistress… Matuchek?” Rupert asked. “That name is from Bohemia, like me.”

“Elsewhere and elsewhen,” she said, “though the words aren’t especially meaningful in this context. That is, I don’t belong to your future. I doubt if your world will look remotely like mine, by the time it reaches its own 1974. Certainly neither world of Holger’s will.”

Rupert stared at the Dane, who puffed his pipe before explaining in a diffident tone: “Well, you see, I’m a peculiar case. I belong—I was born in—a universe where the Carolingian myths are true. You know, Roland and Oliver and the rest.”

“You’re too modest,” Valeria said.

“No, I just don’t want this discussion to get worse complicated,” he replied. To Rupert: “Never mind how, I got cast into an altogether different time-line—a time-line where magic doesn’t work, except maybe in areas like ESP—oh, again, never mind. I’m trying to find my way home. I have had nothing to go on except a spell which carries me through space-time barriers, all right, but doesn’t have any direction to it. After a lot of mishaps—the last was with a clutch of Aztec gods, and I barely escaped in one piece—I’d picked up enough assorted hints and clues that I could fumble myself to this inn. By my good luck, Miss Matuchek was here.”

“I don’t believe that was pure coincidence,” Valeria said. “However, let’s skip that. The point is, Rupert—Holger’s twentieth century and mine are quite alike, rationalistic, industrialized, the Western countries mostly democratic. Only they’re quite unlike, also. For instance, in both of them, the USA and Germany were on opposite sides in the First World War. But his Second World War, that he fought in himself, was against Germany too—and Japan and Italy—while mine, that my parents fought in, was against the Saracen Caliphate. I suppose the differences were mainly due to paraphysical forces. Either they’re as weak in that adopted cosmos of Holger’s as he thinks, or else nobody there has discovered how to degauss the effects of cold iron, as they did in my world about 1900.”